Chicago Mayor Rahm Emanuel responded Wednesday to a two-decade saga of police torture in a way none of his predecessors had done before: He apologized.

A secret unit operating under the direction of former Chicago police commander Jon Burge carried out systemic torture of suspects in criminal cases, mainly African-Americans on Chicago's South Side, to produce false confessions between 1972 and 1991.

While the abuse has been widely documented, Mr. Burge was never criminally prosecuted, despite ongoing accounts of almost 200 men sent to prison based on forced confessions on his watch. Meanwhile, the statute of limitations has run out, preventing Burge from ever facing a criminal trial. He is currently serving a 4-1/2-year prison term for perjury and obstruction of justice charges from a 2010 civil case related to the torture cases.

The City of Chicago has paid millions to settle cases involving Burge. On Wednesday, the city council paid $6.15 million each to two torture victims who were released from prison four years ago. Both men spent 21 years in prison each before their exoneration.

In total, the city has spent about $85 million for settlements and legal fees related to 17 Burge torture cases. Cook County has spent about $10.7 million.

With at least 100 cases pending, the city faces heavy demands for compensation to victims under Burge. Mayor Emanuel has set aside more than $27 million to settle lawsuits for 2013 alone.